Speed-changing mechanism for metal-working machines.



PATEN'I'ED DEC. 12, 1905.

L. S. BURBANK. SPEED CHANGING MECHANISM FOR METAL WORKING MACHINES.

APPLICATION FILED JULY 12. 1905.

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L. S. BUR-BANK.

SPEED CHANGING MECHANISM FOR METAL WORKING MACHINES APPLICATION FILED JULY 12. 1905.

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PATENTED DEC. 12, 1905.

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APPLICATION FILED JULY 12. 1905 4 SHEETS-SHEET 3.

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PATENTED DEC. 12, 1905.- L. s. BURBANK. SPEED CHANGING MECHANISM FOR METAL WORKING MACHINES.

APPLICATION FILED JULY 12. 1905.

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V UNITED STATES PATENT OFFICE.

SPEED-CHANGING MECHANISM FOR METAL-WORKING MACHINES.

Specification of Letters Patent.

Patented Dec. 12, 1905.

Application filed J'uly 12, 1905. Serial No. 269,361.

To aZZ whom, it may concern.-

Be it known that I, LoUIs S. BURBANK, of Worcester, in the county of Worcester and State of Massachusetts, have invented certain new and useful Improvementsin Speed-ChangingMechanismsfor Metal-Working Machines, of which the following is a specification.

This invention has relation to speed-changing mechanisms for metal-working machines, and has for its object to provide such improvements therein that the driven element may be rotated at any predetermined speed that is considered convenient or desirable.

The invention is illustrated as embodied in a lathe or screw-machine; but I desire to have it understood at the outset that it may be equally well embodied in a milling-machine or other form of metal working machine. When the invention is embodied in alathe or screw cutting machine such as illustrated, I utilize in combination with it certain other novel features of construction and arrangement of parts, which I have illustrated upon the drawings and which I hereinafter set forth in detail.

One of the features of the invention is a floating cone of gears. Preferably this cone is held against longitudinal movement and is arranged to coact with an axially-movable driving member or an axially-movable driven member, or both. These driving and driven members, which take the form of gears intermeshing with the cone-gears, are mounted to slide upon shafts and are movable past each other, so that the different combinations which may be effected for securing diflerent speeds is determined by the number of gears inthe cone. This feature of the invention is particularly applicable in lathes or screw-cutting machines, since it makes possible the formation of threads of practically any desired pitch or lead.

Referring to the accompanying drawings, Figure 1 represent in front elevation the head end of a lathe in which my invention is embodied. Fig. 2 represents an endelevation Fig. 3 represents a front elevation of the machine, on a larger scale, with the front of the casing removed and some of the parts in section. Fig. 4 represents a vertical transverse section. Fig. 5 represents a section on the line 5 5 of Fig. 4-with the gears of the, end combination in proper relation to reduce the speed in transmission. Fig. 6

to have it understood that the phraseologywhich I employ isfor the purpose of description and not of limitation and that various changes may be made in the mechanism without departing from the invention. 1

Referring to the drawings, a lathe is illus trated having a bed 20, on which are the leadscrew 21 and the feed-rod 22, each of which is separately driven independently of the other, as will be explained. The spindle 23 on the head-stock is provided with the customary cone of pulleys 124, by which it may be rotated. On the spindle is a gear 25, from which power is transmitted through the speed-.

changing mechanism to the lead-screw or feedrod, as the case may be. Below the spindle 23 is a shaft 24, which is driven from the gear 25 on the spindle by the gears 26 27. (Shown in dotted lines in Figs. 2 and 3.) The gears 26 27 are reversing-gears and provide for effecting the rotation of the shaft 24 in either direction. The gear 26 is shown in Fig. 2 as intermeshing with the gear 25 on the spindle, and the gear 27, which intermeshes with that at 26, as engaging with and driving a gear 28, keyed or otherwise secured upon the shaft 24. The gears 26 27 are journaled upon studshafts supported by a segment 29, the hub of which is pivoted on the shaft 24, as sho wn in dotted lines in Fig. 3. The gear 26 may be engaged with the gear 25 or the gear 27 may be engaged directly with said gear 25, in which event the gear 26 rotates idly. The hub, which is illustrated at 30, has secured to it a second segment 31, to which is attached' a handle 32, provided with a locking-pin 33.

By means of the handle the gears 26 and 27 may be moved into their different operative positions. A bolt 34, passing through a slot 35 in the standard 36 in which the spindle is journaled, provides additional means for looking the segment against movement. This mechanism, although described in detail, is one of the common mechanisms which is utilized in lathes of this character.

1 will now describe an improved change-- is a rod 37 upon which is a quill, sleeve, or

hollow shaft 38, which forms, as it were, an intermediate shaft in the power-transmitting mechanism, and which being driven from the shaft 24 serves to effect the actuation of the floating gear-cone mechanism and which, with respect to the last-named mechanism, may be termed a driving member. This quill or sleeve has keyed or otherwise secured upon it an elongated gear-wheel 39, as best shown in Figs. 3 and 5. This gear is adapted to be driven at different speeds from the shaft 24 by the following mechanism, which is included in the end combination, so called.

Two parallel shafts 40 41, arranged one infront of the other, are supported by the end walls of a removable casing. They are in the nature of stud-shafts, and in the present instance are not adapted to rotate. The shaft 40 has upon it a quill or sleeve 42, in which is keyed a relatively large gear 43', which is slid1 ingly in mesh with the gear 39. The quill has a handle or knob. 44, by which it may be moved longitudinally. The shaft 41 is mounted upon three disks 45, 46, and 47, which are arranged in axial alinement and which are mounted upon studs 48, so that the shaft may be rocked through the arc of a circle into any one of three different positions, the said shaft being passed through curved slots in the walls of the casing which inclose the end combination. Mounted loosely upon a bushing 49, formed on the disk 46, is a pinion 50, to the hub of which is keyed a gear 51. This gear is illustrated in Fig. 5 as intermeshing with and being driven by a gear 52, secured to a quill orsleeve 53, slidingly keyed upon the shaft 24. This sleeve has a handle or knob 54, by which it may be moved.

When the parts are in the position shown in Fig. 5, power is transmitted to the gear 39 from the gear 52 through the gear 51, the pinion 50, and the gear 43, and the gear 39 rotates at one-half the speed of the gear 52; but by moving the shaft 41 to the position shown in Fig. 2that is, to an intermediate position-and sliding the gear 43, power may be transmitted directly from the gear 52 to the gear 43 through the gear 51, and the gears 39 and 52 rotate synchronously, or, again,

by shifting the parts the pinion 50 may be engaged with the gear 52 and the gear 51 may be engaged with the gear 43, so that power will be transmitted from the gear 52 to the gear 50 and from the gear 51 to the gear 43, with the gear 39 rotating at twice the speed of gear 52. Thus it will be seen that by the end combination, as described, the hollow shaft 38 may be driven in either direction at anyone of three different speeds by the use of the gears described.

The shaft 41, which is included in the mechanism, is adapted to be rotated through the arc of a circle into any one of three diiferent positions, according to the well-known geometric proposition that a circle may be drawn through three points. It should be noted that although I secure three different speeds in transmission yet the gears occupy a small space, said space being double the thickness of one of the gears.

The two connected intermediate gears constitute a cone-gear, which is transversely movable, as described, so that the mechanism as a whole is a simple form of the floating conegear mechanism to be hereinafter described for securinga large number of different speeds of the ultimately-driven member of the machine.

Referring now to Figs. 2, 3, and 4, I will describe the floating cone-gear mechanism by which power is transmitted from the hollow shaft 38 to the feed-rod or the lead-screw, as desired. Immediately below the quill or hollow shaft 38 is a hollow shaft 56, which is journaled loosely upon a shaft 57. These two hollow shafts 38 and 56 have slidingly keyed upon them gears 58 59, respectively, said gears being movable longitudinally past each other. practically from one end of their supporting quills or shafts to the other. They are adapted to be engaged by the cone of gears indicated as a whole at 60. This cone is illustrated as comprising eleven gears, which diminish in diameter from left to right; but this arrangement may be'reversed and a greater or less number of gears may be utilized. The

cone of gears is mounted upon a hollow shaft 61, the ends of which are mounted in two pairs of links 62 63 62 63, by which it may be moved toward and from each of the shafts 38 and 56, so as to cause the engagement of any of the gears of the cone with the gears 58 59. The links of each pair have overlapping ends, which are apertured to receive the end of the shaft 61. These links arearranged to slide in guides 64 65, which are mounted loosely upon the rods 37 and 57, respectively. The links themselves are provided with internal rack-teeth, which are adapted to be engaged and moved by partial pinions 66 67 on the said rods 37 57. These guides 64 and 65, which are at the left end of the machine, are provided with hubs which-extend through the end walls of the casing which incloses the mechanism, and keyed upon the ends of the said hubs are the disks 68 69. The two rods 37 and 57 have keyed to their projecting ends handles 70 171, each handle being provided with aspringpressed locking-pin 172,with a knob 173,adapted to engage any one of a series of sockets formed in the disks-68 69. By means of the handles 70 and 171 the rods 37 and 57 may be ro-- tated to shift the links 62 63 and move the floating gear-coneinto proper position to cause the engagement of the gears of the cone with the gears 58 59 in anyposition to which the latter may be moved. The gear-cone will-be locked in the position to which it is moved by engaging the locking-pins 172 with apertures or sockets in the disks 68 69. When the locking-pins are IIO Withdrawn, however,for the purpose of rotating the rods 37 and 57, the disks 68 69 and the guides 64 will be free to rotate about the axes of said rods as the links 62 63 vary their angles with relation to each other. For the purpose of moving the gears 58 and 59 to cause them to intermesh with any predetermined gears of the cone 60 I provide the following mechanism: On a guide-rod 72, arranged in suitable brackets in the front of the casing, is a slide 73, having a yoke 74, which embraces the ends of the hub of the gear 58.

This slide may be moved longitudinally of the guide, and it is provided with a finger 75, which may be engaged with any one of a series of notches 76, formed in the front of the casing. This finger is held in its operative position by a spring-pressed pin 77, which slides along a flat surface 78 on the front part of the casing. The slide has a handle 79, by which it may be moved. By pressing down the handle 79 the finger may be disengaged from one notch and the slide moved along its guide-rod to bring the gear 58 into position to engage any one of the gears on the cone 60, the notches being equal in number to the gears and registering therewith, as shown in Fig. 1. The gear 59 is moved by a similar slide 80 upon a guide-rod 81 with a yoke 82, a finger 83, and a handle 84, as just described. The notches 85 on the casing for the finger 83 are likewise equal in number to the gears on the cone 60, and they are arranged to register therewith so as to hold the gear 59 in position to be engaged by any one of the gears of the cone. Each location of the slides is designated by a symbol, such as a numeral, there being, as stated, eleven different locations for each of the slides. The two scales are indicated at 91. On the upper scale 91, above the row of numerals indicating the different positions of the slide 7 3, are other rows of numerals,

- which indicate the threads which may be cut when the slides are in different positions, and opposite each row is a smaller numeral, as 2 or 7, which indicates the correct position for the lower slide 80. For instance, if the lower slide be placed at 2 on the scale 90 and the upper slide be. placed at 5 then sixteen threads to the inch will be cut, provided the end combination be so set that the gear 43 is driven directly from the gear 52 by the pinion 50. By changing the end combination, however, to vary the speed of transmission threads may be cut which will be onehalf of sixteen--that is, eightor twice sixteen-that is, thirty-two. If it be desired to cut, for instance, thirteen threads to the inch, then the lower slide will be placed at 7 and the upper slide at 10. It will be apparent that a large number of rows of numerals may,

. if desired, be placed upon the scale-plate 91 I have already stated that I may employ a lead-screw 21 and a feed-rod 22. It will be observed from Fig. 1 that on the lead-screw 21 there is a gear 92 and that a gear 93 is on the feed-rod 22. A clutch mechanism 94 is interposed between the gear 93 and the rod 22, the clutch being illustrated in Figs. 1 and 3 as open. A shaft 95 is journaled in the casing of the power-transmitting mechanism, and it is driven by gears 96 97 on the said shaft 95 and the hollow shaft 56. The shaft 95 is adapted to slide in its bearings and is provided with a knob 98 for this purpose. Upon its other end it has a gear 99, which is adapted to be engaged with either thegears 92 or 93. In Fig. 3 the shaft 95 is shown in position to cause the transmission of power from the hol-- low shaft 56 to the lead-screw; but it will be understood that the gear 93 may be clutched to the feed-rod 22 and the shaft 95 be shifted to cause the gear 99 to engage the gear 93, whereby power will be transmitted from the hollow shaft 56 to the feed-rod 22, in this event the gear 99 being disengaged from the gear 92.

The end combination, (so called,) including the gears 52 and 4:3 and the floating cone-- gear 50 51, is inclosed in a casing which is shown in end view in Fig. 2 and is indicated as a whole at a. This casing is removable from the end of the lathe, and it comprises the outer plate a and the inner plate M. The removability of this casing with the mechanism which is mounted therein permits the utilization of other transmitting-gearing, if it be desired. The floating gear-cone powertransmitting mechanism in the front of the machine is likewise inclosed in a removable casing, which is indicated at b, and comprises a front portion 6 and a rear portion 5 The front portion 6 is divided from the rear portion 6 on a plane coincident with the axes of the hollow shafts 38 and 56. In Fig. 3 this front portion of the casing is illustrated as removed, as may be done in practice, to expose the gearing to View for repairs or the like. I shall not attempt to describe in detail the exact construction of these casings a and b or the exact means by which they are attached to the lathe, although it should be remembered, as previously stated, that they are both removable, so that considered by themselves they are in the nature of lathe attachments. Thus when a lathe is equipped with these attachments they may be removed in case of need to permit other mechanism to be utilized for driving the feed-rod or lead-screw in any convenient manner from the spindle.

In the operation of the mechanism which I have herein described it will be apparent that in the floating-cone mechanism the links 63 may be actuated independently of the links 62 by means of the pinion 67 and the handle 71 with the intervening devices and that the links 62 may beadjusted independently of the links 63. In other words, the cone may be adjusted toward and from either of the rods 37 or 67 without moving it toward and from the axis of the other of said rods. This is frequently desirable, since it is often necessary to shift the upper slide 73 and the gear 58 without moving the lower gear 59 and the slide 80, or vice versa. In such cases, therefore, it is necessary to adjust the cone toward and from the axis of the shifted gear. I sometimes find it desirable to utilize in lieu of the separate leadscrew 21 and feed-rod 22 a single combined feed-rod and lead-screw, and I would not regard it as a departure from my invention should such a device be utilized. Again, as I have previously stated, the end combination inclosed within the casing a may be removed, and I have illustrated in Fig. 6 a form of change-gearing which may be used in lieu of the gearing in the end combination. hen the end combination is removed,the stud-shaft 40, the shaft 41, and the gears 43, 50, 51, and 52 are all removed. Then upon the shaft 24 may be placed a segment 200, as shown in Fig.

6. This segment may have a handle 201 and being mounted loosely upon the shaft 24 is adapted to be rocked in one direction or the other. This segment has a slot 202, which is radial relatively to the shaft 2 1, so that there may be adjustably secured to it a stud-shaft 203, carrying an idler or change-gear 204 of any desired diameter. This gear intermeshes with and is driven by a change-gear 205, which is keyed upon the shaft 24. The idler 204 may be caused to intermesh directly with the elongated gear 39 on the hollow shaft 38, or else the idler 204: may be caused to intermesh with the gear 96 on the shaft 95 to drive it directly and not through the floating-cone mechanism. Any change-gears may be utilized in lieu of those at 205 204, and their diameters may be in such ratio as to impart the proper speed of rotation to the ultimately-driven shaft. The segment 200 has an arcuate slot 206, through which a bolt 207 may be passed into the end of the lathe. In Fig. 6 the parts are shown on a scale somewhat smaller than the scale of the parts in Fig. 2. Another feature of the invention which may be more elaborated resides in the notched plates 76 85. These may be constructed so as to be reversible, or interchangeable notched plates may be substituted therefor. Consequently in lieu of providing all of the eleven notches, as illustrated, the plate may have, for instance, only the notches corresponding to the notches 2 and 7 on the scale 90,or they may have any predetermined number of notches which are most often used.

Having thus explained the nature of the invention and described a way of constructing and using the same, although without attempting to set forth all of the forms in which it may be made or all of the modes of its use, I declare that what I claim is 1. In speed-changing mechanism, a gearcone having gears of different diameter and means by which said cone may be adjusted transversely in any direction.

2. In speed-changing mechanism, an axiallymovable rotary driving member, an axially-movable rotary driven member, means for moving said members independently of each other a rotary cone having power-transmitting members of different diameters, and means by which said cone may be adjusted toward and from the axes of the driving and driven members.

3. In speed-changing mechanism, the combination with driving and driven shafts arranged in parallelism, of longitudinally-adj ustable gear-Wheels on said shafts, means for moving said gear-wheels independently of each other aradially-adjustable gear-cone, and means for adjusting said gear-cone toward or from said shafts in intersecting lines.

4:. In speed-changing mechanism, the combination with driving and driven shafts arranged in parallelism, of longitudinally-adjustable gear-wheels on said shafts, a radiallyadjustable gear-cone, adjustable links connecting said gear-cone and shafts, means for adjusting said links, and means for adjusting said gear-wheels and holding them to their adjustment relative to said gear-cone.

5. In speed-changing mechanism, the combination with a shaft and its adjustable gearwheel, of an adjustable gear-cone axially parallel to said shaft, links connecting said gearcone and shaft, means for adjusting said-links, and means for holding them to their adjustment.

6. In speed-changing mechanism, the combination with parallel hollow shafts, longitudinallyadjustable gearwheels thereon, and inner shafts within said hollow shafts, of an intermediate gear cone, jointed adjustable links connecting said gear cone and inner shafts, and means for adjusting said links and gear-cone.

7. In speed-changing mechanism, the combination of parallel shafts longitudinally-adjustable gear-Wheels thereon, and means for transmitting power from one of said shafts to the other comprising an intermediate floating gear-cone, means for adjustably connecting said gear-cone and shafts, and means for securing the said elements after adjustment.

8. In speed-changing mechanism, afloating gear-cone, links for adjusting said cone in any direction transversely of its axis, and means for actuating said links.

9. In speed-changing mechanism, a floating gear-cone, links for adjusting said cone in any direction transversely of its axis, racks on said links, and gears for moving said racks.

- 10. In speed-changing mechanism, the combination with a shaft a longitudinally-adjustable gear thereon, of a radially adjustable gear-cone, and adjustable links for adjusting said gear-cone relatively to said shaft.

11. In speed-changing mechanism, the combination with a shaft, and means for driving the same, of a longitudinally-adjustable gear on said shaft, a radially-adjustable gear-cone, adjustable links in connection with said gearcone and said shaft, and means for adjusting said links, substantially as specified.

12. In speed-changing mechanism, the combination with a hollow shaft an adjustable gear-wheel thereon, an inner shaft and one or 'more pinions on said inner shaft, of a radiallyadjustable gear-cone, adjustable links and one or more racks on said llnks engaging said pinion or pinions.

13. In speed-changing mechanism, the combination with a hollow shaft an adjustable gearwheel thereon, an inner shaft and pinions on said inner shaft, of a radially-adjustable gearcone, adjustable links racks connected to said links engaging said pinions, and a locking device for locking the pinions and the racks against relative movement. e

14. In speed-changing mechanism, driving and driven shafts arranged in parallelism, a gear-cone adjustable toward and from said shafts about the axes of said shafts, gears on said shafts adapted to he engaged by the gearcone, and means for adjusting said gears independently of each other along their respective shafts and locking them in their adjusted positions.

15. In speed-changing mechanism, a floating gear-cone, toothed links for adjustably supporting said gear-cone, a shaft pinions fast on said shaft and engaging said toothed links, guides on said shaft for said links, and means for locking said shaft and said guides against relative rotary movement.

16. Inspeed-changing mechanism, a floating gear-cone, a toothed link supporting one end of said cone, a shaft a pinion fast on said shaft engaging. the toothed link, a guide loose on said shaft a locking-plate rigidly secured to said guide, a handle fast on said shaft and means on the handle for engaging said locking-plate.

17. In a lathe, the combination with the floating gear-cone and the independently-adjustable driving and driven gears which cooperate therewith and means for adjusting said cone about the axes of said gears, of means for transmitting power to the drivinggear, comprising an axially-movable driving gear, an axially-movable driven gear,and rigidly-connected gears movable transversely of their axes.

18. In a lathe. the combination with the floating gear-cone and the independently-adjustable driving and driven gears which cooperate therewith and means for adjusting said cone about the axes of said gears, of means for transmitting power to the drivinggear, comprising an axially-movable drivinggear, and an axially movable driven gear which are adjustable independently of each other, rigidly-connected gears movable transversely of their axes in the arc of a circle into three different positions-whereby three different speeds of the driven gear may be obtained, and means for securing said transverselymovable connected gears after adjustment.

19. Aspeed-changing attachmentforalathe comprising a driving-gear, a driven gear, said gears being separately and independently adjustableaxially and rigidly-connected intermediate gears of different diameters transversely movable into different positions said driving, driven, and intermediate gears having their axes located at the apexes of a triangle, whereby any one of said intermediate gears may be intermeshed with either of the.

driving and driven gears.

20. A speed-changing attachment for a lathe comprising an axially-movable driving-gear, an axially-movable driven gear, rigidly-connected intermediate gears of different diameters transversely movable into different po sitions whereby any one of said intermediate gears may be intermeshed with either of the driving and driven gears said driving, driven and intermediate gears having their axes at the apexes of a triangle, and means for rigidly securing said intermediate gears in the position to which they are adjusted.

21. A speed-changing device comprising two mechanisms geared together, each mechanism comprising a transversely movable gear-cone and independently axially movable driving and driven gears each adapted to be engaged with any gear of the cone, whereby the speed of the ultimately-driven member may be changed by either of said mechanisms.

22. In a lathe, the combination with the floating gear-cone and the driving and driven gears which cooperate therewith, of a spindle, and interchangeable mechanisms adapted to be inserted between the driving-gear and the spindle, one of said interchangeable mechanisms consisting of a floating cone with driving and driven gears and the other consisting of a swinging support, a driving-gear and an idler, substantially as described.

23. In a lathe, the combination witha variable-speed gearing and a driving-shaft, of interchangeable mechanisms for actuating said variable speed gearing, one of said interchangeable mechanisms comprising independently axially adjustable driving and driven gears, and a transversely-movable gear-cone, all bodily removable, with the driving-gear adapted to be attached to said driving-shaft, and the other of said interchangeable mechanisms comprising removable change-gears of which one is adapted to be attached to said driving-shaft.

24:. In a lathe, a variable-speed gearing, comprising a driving-gear and a driven gear which are axially adjustable separately and independently of each other, into either of two positions, two rigidly-connected intermediate gears of diiferent diameters, means by which said intermediate gears may be adjusted transversely into three different positions, in consequence of which the larger intermediate gear may be engaged with the driving and driven gears, or the larger intermediate gear and the smaller intermediate gear may be engaged with the driving and the driven gears respectively, or the larger lntermediate gear and the smaller intermediate gear may be engaged with the driven and the driving-gears respectively to secure three diiferent speeds of the driven gear, as described.

25. In a lathe, the combination with driving and driven shafts, of a removable changespeed mechanism adapted to be interposed between said shafts, comprising a casing or support adapted to be removably attached to a lathe, three hollow shafts or members, as at.

53, 49 and 42, of which one, as at 53, is adapted to be keyed on the driving-shaft, driving and driven gears, as at 52 and 43, on said members, as 53 and 4:2, and adjustable axially independently of each other, intermediate gears of difierent diameters on one of said members, as 4:9,and means for pivoting said last-mentioned member 49 on an eccentric axis, all combined substantially as set forth.

and driven shafts arranged in parallelism, a gear-cone adjustable toward and from said shafts, gears on said shafts adapted to be engaged by the gear-cone, means for adjusting said gears independently of each other along their respective shafts, locking devices adjustable with said gears, and notched plates adapted to coact with saidlocking devices.

27. In speed-changing mechanism, driving and driven shafts arranged in parallelism, a

26. In speed-changing mechanism, driving gear-cone adjustable toward and from said 

